Thread controlling device for cross thread laying mechanisms



Sept 12, 1933. J. R. MOFFATT 1,926,954

THREAD CONTROLLING DEVICE FOR CROSS THREAD LAYING MECHANISMS Original Filed July 19, 1928 5 Sheets-Sheet l p 1933- J. R. MOFFATT 1,926,954

THREAD CONTROLLING DEVICE FOR CROSS THREAD LAYING MECHANISMS Original Filed July 19. 1928' 5 Sheets-Sheet 2 j] I BEE 9 V 3 9 [91 I (97 O l a J 42 ii M w" I HI f U, I 26 1 J7 I Z9 25 0 gvvoentoz Sept. 12, R MQFFATT THREAD CONTROLLING DEVICE FOR CROSS THREAD LAYING MECHANISMS Original Filed July 19, 1928 5 Sheets-Sheet 3 Sept. 12, R Q ATT THREAD CONTROLLING DEVICE FOR CROSS THREAD LAYING MECHANISMS Original Filed July 19, 1928 ,5 Sheets-Sheet 4 Sept. 12, 1933.

J. R. MOFFATT THREAD CONTROLLING DEVICE FOR CROSS THREAD LAYING MECHANISMS Original Filed July 19, 1928 5 Sheets-Shet 5 Patented Sept. 12, 1933 V UNITED STATES PATENT OFFME "1,926,554 7 I I V THREAD CONTROLLING .DEVICE Fon onoss THREAD LAYING MECHANISMS,

James R. Mofiatt; Chicago, Ill.,- assignor to Union Special Machine Company, Chicago, 111., incorporation of Illinois- Original application July 15 1928, Serial No.

294,009. Divided and this application May 15, 1930. Serial N07 452,683

9 claims; (01. 112-245) V reciprocating member cooperating with thread guides carries independent devices operating in succession totake up and give up thread for each reciprocation A further of said member.

object of the invention is to provide a threadcontrolling mechanism which when operated in connection with a cross thread laying mechanism takes up the slack in the cross thread and places the cross thread under ten--v sion as the cross thread loop is completed so as to insure the proper positioning of the cross thread for th eneedles to pass the same.

- A still further-object of the'invention is to provide-a thread controlling mechanism which when operated with a cross thread laying mechanism takes up saidcross threadafter the completion of the cross thread loop for drawing the cross thread taut with the. final stitch formation.

These and other objects will in part be obvious and will in part be'hereinafter more fully dis,-

= closed.

In the drawings which show byfway of illustration one embodiment of thei nventi on:

Fig. '1' is, a

front view of a par-t'of a machine embodying the improvements.

Fig. 2 is a chine.

Fig. 3 is an en chine.

rear view of a portion of the maview of a portionof theima for forming a loop in the crossthread, and means for supporting and actuating the same withrthe parts in position for completing thexcross thread loop.

Fig. 5 is a similar view but showing the parts positioned'for the loop forming device to engage the crossthread.

Fig. 6 is a front view showing more or less diagrammatically the needles, the, cross thread guide, and the hookend of the loop forming de Fig. 71's an enlarged diagrammatic -view showing the needle threads and the crossthread. formed into loops and locked thereby;

Fig. 8 is a View showing the thread controlling means for the cross thread in side elevation with the needle bar at .the upper end of its stroke.

' Fig. 9 is a similar view but showing i in-full lines theneedle bar at the lower end of its stroke and in broken lines the cross thread controlling element as having completed its take-up action on the up-stroke of the needle bar;

Fig. 10 is a detail in plan showing the cross thread controlling means.

The invention is directed to devices for control- .lingthe thread'in a stitch forming mechanism.

the cross thread a'loop which is laid so. that it entered by the two needles farthest disposed fromthe cross thread guide, while the other .needle. passes outside of. the cross threadv loop and secures the cross thread by laying its own needle; thread over the shank of theicross thread. loop; v

This cross thread laying mechanism shown'in thedrawings forms the subject matter of my 00-' pending application, of which this isa division.

The invention herein is directed particularly as noted to the thread controlling mechanismi This thread controlling mechanism includes a cam shaped plate which is so disposed relative to stationary thread guides .as to move'into engagement with the thread passing through the guides it and pull the same from the supply. In connection with a cross thread laying mechanism the drawing up of the cross thread occurs at the time when the loop forming device moves into engagement with the cross thread. The. controlling member for the thread is also provided with another. cam shaped portion which engages the thread and places the same under tension. These devices operate in succession on the thread to take up and give up the. same for each reciprocation of the controlling'device. In connection with the. crossYthread-laying mechanism the thread is placed under tension at the time when the cross thread loop is completed and this insures that the strands of the cross thread loop will be taut and properly positioned relative to the needle. The above controls on the thread take place while the controlling mechanism is moving in one direction. While it is moving in the opposite direction then the cam plate again engages the thread passing between the guides and takes up the slack therein. In connection with a cross thread laying mechanism this occurs after the cross thread loop is formed and draws the cross thread loop comparatively taut in the stitch formation.

Referring more in detail to the drawings the invention will be described as applied to a cross thread laying mechanism but it is understood that it may be used in connection with other elements of the stitch forming mechanism. The thread controlling devices are applied to a sewing machine having the usual form of work support 1, overhanging arm 2 carrying a needle bar 3 provided with three needles 4, 5 and 6. C0- operating with these needles is the ordinary thread carrying looper. The needle bar is reciprocated by means of a needle lever 7 connected by a link 8 to the needle bar. The needle threads are indicated at n in the drawings. The needle threads on the upper face of the fabric are joined by a cross thread laid into loops. The cross thread is indicated at c. This cross thread passes from the supply through a suitable thread guide 9, and thence toan eye 10 in a member 11 secured to the overhanging arm. This member 11 is stationary. As clearly shown in Fig. 10 of the drawings the member 11 is provided with a U-shaped portion 12. Opposite the thread eye 10 is a second thread eye 13. The cross thread 0 passes first through the eye 10 and then the eye 13. This cross thread is then led to a movable cross thread guide 14. Said cross thread guide is provided with an eye 15 back from the end thereof and an eye 16 at the end thereof. The cross thread guide 14, as clearly shown in Figs. 4 and 5, is carried by an arm 17 which is L-shaped. This arm is pivotally mounted at 18 on a projecting arm 19 carried by a sleeve 20 which is mounted for free oscillation in a horizontal plane about the guide bar 21 which is associated-with the presser bar 22. Mounted on the lower end of the presser bar 22 is a presser foot 23 and cooperating with this presser foot is a feeding mechanism which includes a feed dog 24.

lhe sleeve 20 is provided with a projecting arm 25. This projecting arm 25 carries a member 26 having a notched end 27. This notch faces outwardly and engages the cross thread running through the cross thread guide for forming a loop'therein. The loop forming member 26, as noted, is carried'by the arm 25 and when this arm is oscillated, the notched end of the loop forming member will move in a curved path about the axis of the guide bar 21 as a center. This curved path lies in front of the needles and extends from a point at one side of the needles to a point at the other side thereof, as clearly shown in 4 and 5. Mounted on the overhanging arm is a shaft 28. This shaft 28 is arranged with its axis vertical. The shaft carries an arm 29 and the arm 29 is pivoted at 30'to the elbow of the arm 17 This shaft 28 is oscillated by means of a link Bl which; in turn, is connected to an arm 32 carried by a horizontal cross shaft 83. This cross shaft 33 carries an arm 34 with which an "eccentric strap 35 cooperates. The eccentric strap is actuated by an eccentric on the main shaft beneath the work support.

In Fig. 5 of the drawings the thread guide is shown at the forward end of its stroke and the loop forming member about to engage the cross thread. When the arm 29 is oscillated said arm and the portion of the L-shaped member 17 between the pivotal point 30 and the pivotal point 18 will move toward alignment as clearly shown in Fig. 4. As these arms move nearer alignment it will force the arm 19 to the left and cause the sleeve 20 to turn in a clockwise direction about the center of the guide bar 21. This imparts a movement to the member 26 which carries the hook end thereof into engagement with the cross thread and forms in the cross thread a loop as clearly shown in Fig. 4. During this formation of the cross thread loop the cross thread guide is moving toward the rear of the machine. The end of the arm 1'7 will move rearwardly in a curved path about the center of the guide bar 21. The pivotal connection 30 between the arm 29 and the arm 17 will also move rearwardly in a curved path about the axis of the shaft 28 as a center. This combined rearward movement of the pivotal point 18 and the pivotal point 30 in the arm 17 brings about a substantially right line movement in the eye 16 at the end'of the cross thread guide member which is parallel with the line of feed and at one side of the needles. This positions the thread eye 16 slightly in rear of a line passing through the three needles at right angles to the line of feed.

The strand of the cross thread loop running from the hook end of the oscillating member 26 to the eye 16 will be laid, therefore, in front of the two left hand needles as viewed in Fig. 4 and in rear of the right hand needle. Theneedles are preferably set with their points at different levels as shown in Fig. 1. This strand of the cross thread is laid against the front face of the Ill) middle needle and carried past the right hand 7 needle beneath the point thereof which is set higher so that the middle needle will, in a measure, aid in the proper positioning of this strand of the cross thread loop. The other strand of' the cross thread'loop, of course, runs from the hook end of the oscillating member 26 to the previously formed stitches. As clearly shown in Fig. 7 the cross thread 0 is formed into a series of loops. tween the hook end of the oscillating member 26 and the eye 16 of the cross thread guide. The strand 0 is the strand running from the hook end of the member 26 to the previous stitch.

The needle thread loops of the needle 4 are The strand 0 is the one running 'beindicated at n the needle thread loops'of the needle 5 are indicated at n the needle thread loops of the needle 6 are indicated at n and thefabric is indicated at F.

. The operation of the cross thread laying mechanism described above will be obvious from the description given. The thread controlling devices for the cross thread include a cam plate 36 mounted on the needle bar and reciprocating beneedle bar as indicated at 40, and terminates in a hook shaped cam portion 41. When the parts are positioned as shown in Fig. 9 the needles are at the lower .endof their stroke and the device for forming a-loop in the cross thread is at the rear end of its stroke as shown in Fig.5;

As the needle bar. moves up the loop forming device engages the cross thread and begins the formation of thecross thread loop. Ihe inclined. face 38 of thecamplate engages the cross thread.-

end :of its stroke theloop forming device has reached the end of its'forward stroke and; is

positionedasishown in Fig. 4. Atthis time the.

cross thread loop has been fully formed and properly positioned for the needles topass the strands in the cross-thread loop. The cam por'" tionv 41 of the plate 36 engages the cross thread. and takes the slack out of the cross thread as the ity of needles carried thereby, a cross thread needle reaches theupper" end of its stroke. .At this time the cross thread is passed inifront' of'the needlethread of the needle 6 (see Fig. l)

Thistautstrand of the cross thread will hold the needle thread. back so that when the needle 6 descends it will, with certainty, pass in front of V the cross thread. It is true that slack is given to the cross thread as soonas the needle begins its downward movement, but the needle point only moves avery slight distance above this cross thread, and therefore it will pass the cross thread before any appreciable slack is given thereto. On

be substantially taut within the needle threads.-

This cross thread controlling means is of par; ticular advantage in connection with the cross thread laying mechanism described, wherein the cross thread loop is formed by a single loop forming device as the thread is drawn from the supply to enable the loop forming device to form its loop without undue .strain upon'the crossv thread. It also insures that the cross thread will be taut at the time that this loop forming device and thecross thread guide cooperating therewith are positioning the strand of the loop in a certain desired relation to the path of the needles, and it is of further advantage in the drawing of the cross thread loop taut when released by this loop forming device which has a relatively long movement in the forming of the cross thread loop.

WhileI have described above my improved thread controlling mechanism as it is used in conjunction witha cross thread layinginecha nism for controlling the cross thread in the formation of the cross thread loop, it will be understood that it may be used-with other elements of a stitch forming mechanism such as a needle or a threaded looper. 7 I

In the operation of the thread controlling mechanism for each reciprocation of the member carrying. the threadengaging devices,. said devices operate in succession to take up and give up thread. This is particularly useful-in connest-ion with a looper. where it is essential to take up the thread as the looper moves forward toenter theheedle thread loop and to give up thread as the looper moves on to the end oiitsv stroke in the needle ithread loop and to again take upthread on the first part of the retracting stroke of the looper'and giveup thread after the needle iswell into the looper threadloop so'asto permit thelooper to move to the rear end of its stroke.

dependent'devices for operating in succession to.

. accomplish this taking up andgiving up oi the thread. It is'cbvious that minor changes in the details of construction maybe made without departing from the spirit of the invention as set forth in the appended claims. r

p Having fully described my invention,a-what I.

claim as new and desire to secure by Letters Patent, is:-

I his may be acccniplished by my improved thread controlling mechanism wherein. the reciprocating member is provided with in- ,1. The combination of a needle barge. plural V for the, cross thread includingmeans .for inter.-

mittently engaging the cross thread for drawing the same from the supply on the upward movement of the needle ban.

2. The combination ofaneedle bar, aiplurality of needles carried thereby, a cross threadlaying mechanism including devices for forming a loop in a cross thread, and controlling devices for the cross: thread includingmeans separate from the. loop forming. devices-for engaging the cross thread for taking up the slack therein and drawing said cross thread taut when the loop forming devices complete the formation of the loop in the cross thread, so that said cross thread will prop erly position the needle thread of the right-hand needle and insure that said thread passes in front of the cross thread on its down stroke- '3. The'combination of a needle bar, aplurality of needles carried thereby, a cross thread laying mechanism including devices' for forming a loop in a cross thread, and controlling devices forthe cross thread including means for engaging the cross thread and drawingthe same from the supply on the upward movement of the needle bar and for taking up the slack in the cross thread as the loop forming device reaches the forward end of its stroke and for taking up the slack in the cross thread'loop'and for drawing the formed loop .taut about the needle thread as said cross. thread loop is released by theloop forming device.

4. The combination of a needle bar, a plurality controlling means including a member reciproeating with the needle bar and operating to take up the cross thread, then give slack to the cross 7 thread, andfinally to again take up the cross v 'thread during each cycle of operation ofthe cross thread laying mechanism.

' 5. The combination of aneedle bar, a plurality of needles carried thereby, a cross thread laying mechanism therefor including a cross thread guide movable in a line at oneside of the needles and'a cross thread loop forming device oscillating mechanism therefor including a cross thread guide movable in a line at one sideof the needles and a cross thread loop forming device oscillating in a curved path in front of the needles, a controlling cam plate for the cross thread, stationary guides at each side thereof for directing the cross thread, said plate being shaped so as to engage the cross thread and draw thread from the supply on the upward movement of the needle bar, said cam plate also engaging the cross thread for taking up the cross thread when the loop forming device reaches the forward end of its stroke and holding the cross thread taut as the needles are passing the cross thread and certain of said needles are entering into the cross thread loop.

- '7. The combination of a needle bar, a plurality of needles carried thereby, a cross thread laying mechanism therefor including a cross thread guide movable in a line at' one side of the needles and a cross thread loop forming device oscillating in a curved path in front of the needles, a controlling cam plate for the cross thread, stationary guides at each side thereof for directing the cross thread, said plate being shaped so as to engage the cross thread and draw thread from the supply on the upward movement of 'the needle bar, said cam plate being also shaped so as to engage the cross thread on the downward movement of the needle bar for taking up the slack in the cross thread and drawing the formed cross thread loop taut about the needle threads as it is released by the loop forming device.v

8. The combination of a needle bar, a plurality of needles carried thereby, a cross thread laying mechanism therefor including a cross thread guide movable in a line at one side of the needles and a cross thread loop forming device oscillating ina curved path in front of the needles, a controlling cam plate for the cross thread, stationary guides at each side thereof for directing the cross thread, said plate being shaped so as to engage the cross thread and draw thread from the supply on the upward movement of the needle bar, said cam plate also engaging the cross thread for taking up the cross thread when the loop forming device reaches the forward end of its stroke and holding the cross thread taut as the needles are passing the cross thread and certain of said needles are entering into the cross thread loop, said cam plate also engaging said cross thread on the downward movement of the needle bar for taking up the slack in the cross thread and drawing said formed loop taut about the needle threads as it is released by the loop form ing device.

. 9. In a thread controlling mechanism for sew-' ing machines, the combination of spaced thread guides, a reciprocating member, a cam plate carried by said reciprocating member and adapted to move between said thread guides, said cam plate being provided with independent devices operating in succession, one of which takes up and gives up thread for each up and down stroke of'the needle, and the other of which takesup thread on the up stroke of the needle and gives up thread on the down stroke thereof.

JAMES R. MOFFATT. 

